* {
  margin: 0;
  padding: 0;
}
body {
  position: relative;
  background-image: linear-gradient(to right, #be93c5, #7bc6cc);
  animation-name: show;
  animation-duration: 1.5s;
}
@keyframes show {
  0% {
    opacity: 0;
  }
  100% {
    opacity: 1;
  }
}
ul li {
  text-decoration: none;
}
a {
  display: inline-block;
  text-decoration: none;
  color: #333;
}
@media screen and (max-width: 1240px) {
  .head h1 {
    font-size: 36px ;
  }
  .aside {
    font-size: 14px;
  }
}
@media screen and (max-width: 768px) {
  .aside {
    width: 100px;
  }
}
@media screen and (max-width: 488px) {
  .head h1 {
    font-size: 22px;
  }
  .aside {
    font-size: 1px;
  }
}
.head {
  position: relative;
  width: 100%;
  height: 13vh;
}
.head h1 {
  margin-left: 8vw;
  line-height: 13vh;
  font-weight: 100;
  color: #fff;
}
.head .return-btn {
  position: absolute;
  top: 1vh;
  left: 1vw;
  padding: 0 10px;
  border: 1px solid transparent;
  font-size: 26px;
  cursor: pointer;
  background-color: transparent;
  transition: 0.3s;
  color: #fff;
}
.head .return-btn:hover {
  border: 1px solid transparent;
  background-color: rgba(250, 250, 250, 0.774);
  color: #333;
}
.aside {
  position: absolute;
  left: 0;
  width: 25vw;
  height: auto;
  cursor: pointer;
}
.aside ul li {
  width: 13vw;
  height: 50px;
  line-height: 50px;
  text-align: center;
  background-color: #d8e8f0dc;
}
.aside ul li a {
  width: 100%;
  height: 100%;
}
.aside .homepage {
  transition: 0.3s;
}
.aside .homepage:hover {
  background-color: #fff;
}
.aside .pull-down-all {
  height: 50px;
  transition: 0.3s;
}
.aside .pull-down-all .pull-down-btn {
  position: relative;
  height: 50px;
}
.aside .pull-down-all .pull-down-btn::after {
  position: absolute;
  right: 12px;
  top: -4px;
  content: '‿';
}
.aside .pull-down-all .pull-down {
  display: none;
}
.aside .pull-down-all .pull-down li {
  transition: 0.3s;
}
.aside .pull-down-all .pull-down li:hover {
  background-color: #9fd7db;
}
.content {
  position: absolute;
  right: 0;
  width: 75vw;
  height: 82vh;
}
